This invention relates in general to audio-to-video converters and in particular to such converter-modulator devices which display a changing multicolored pattern on a television receiver.
There are various audio-to-video converting devices. Possibly one of the more basic devices is the circuit which divides the incoming audio into frequency bands with each frequency band corresponding to a particular group of like-colored lights, such as on a Christmas tree. As the audio varies, the various corresponding colored lights will be illuminated in a type of rythymic pattern representative of the audio.
With other devices this random grouping of colored lights has been replaced by a color television receiver and random illumination has been replaced by the creation of specific patterns. The following list of patents are representative of some of these devices:
______________________________________ Patent No. Patentee Issue Date ______________________________________ 2,804,500 Giacoletto 8/27/57 3,604,852 Weintraub 9/14/71 3,627,912 Hearn 12/14/71 3,723,652 Alles et al. 3/27/73 ______________________________________
Giacoletto discloses a system which divides the incoming audio into three frequency-color sections and each frequency-color section corresponds to a particular static banded pattern. The number of color bands increases as a function of frequency within the particular section. When a complex musical signal is present, these individual color bands will not be individually seen, but will be accumulated in a complex changing and random pattern.
Weintraub discloses an apparatus for visually displaying aesthetic configurations representative of sound including multicolor kinescope displays in which the degree of sharp curvatures or discontinuities is substantially reduced by jointly varying beam intensity and beam deflection as a function of sound spectral content. The color traces which result are actually Lissajous type figures wherein the color green is represented by a horizontally extended dotted line oval trace, corresponding to audio in the low frequency range. The color blue, corresponding to mid-range audio frequencies, is represented by a solid circular trace. The final color, red, corresponds to high frequency audio and is represented by a vertically extending oval trace.
Hearn discloses an apparatus and modifying circuit for use in conjunction with the conventional color cathode ray tube to provide fanciful wide-band vector representations of video signals. A variety of highly detailed patterns can be created but the display is limited to an outwardly radiating series of lines whose direction is controlled by X (horizontal) and Y (vertical) deflection.
Alles et al. discloses an audio-visual interface network for transforming audio signals from an audio source into a form suitable for reception and visual display by an "unaltered" television receiver. The incoming audio is separated into a plurality of different frequency bands and each group of signals are further processed by a resistor network with the result being a series of nine filtered, rectified and smoothed audio output signals. These nine output signals are used as the nine positions on a plurality of rotary switches, and the pattern generated is in part controlled by the various rotary switch settings. There is a second series of rotary switches and a particular audio pattern may be displayed in a variety of ways, depending on the particular combination of rotary switch settings selected. This particular device uses variable-duration monostable multivibrators and asymmetric phase-shifted square wave signals and the result is a kaleidoscopic pattern. There is no vertical drive capability disclosed, only horizontal bar widths, and the pictorial patterns are generally of a random nature without vertical blanking or sync pulses.
The purpose of these types of devices is to create means by which a changing audio signal can be transformed into particularly interesting and visually pleasing display patterns. The greater the pattern variety, the more interesting such device will remain over a long period of time. In addition to an interesting pattern, it would be desirable to design a low-cost device and a device which had a minimum of required operator controls. Furthermore, it is desirable to provide ample color areas so that the display is easily visible. The devices of Weintraub and Hearn are only line representations which are visually stationary about a center point. Neither of these patterns have the degree of color content (in large areas) which provides a desirable display, and the pattern variety is quite limited. The device of Giacolleto is a random blending of three colors whose color band alignments are fixed and the only variation is in the width of the color bands and how the three colors overlap. Audio volume does not affect the pattern and there is neither uniformity to the pattern nor are pleasing geometric shapes created.
The device of Alles et al. provides greater pattern variation but this is done by means of numerous rotary switch settings which must be selected by the operator. The disadvantage with this type of device is that pattern variety is quite limited unless the various settings are changed and this requires greater interaction by the operator. Various signals are either not generated or not used, such as vertical drive, which could add to pattern variety in a more automatic manner without requiring the extensive manual involvement which the device currently necessitates. Furthermore, the resultant pattern of Alles et al. is kaleidoscopic in nature, and the random display is not modulated in a symmetrical fashion which permits a more balanced display equally occupying the majority of the displaying area.
A further audio-to-video device is currently offered by Atari, Inc. and is identified as "Video Music." This device uses three different shapes which alternate randomly, or one may be selected, and operator controls are used to change the size of the pattern. Further pushbuttons select the rate at which the pattern changes.
None of the devices which have been mentioned provide means by which bass and treble can be accommodated so that the corresponding low and high frequency colors do not dominate the pattern being displayed. Similarly, none of these devices provide elliptical area patterns which are in a vertical stack and roll upwardly at a predetermined rate. Nor do any of these devices incorporate CMOS logic devices as pulse width modulators. None of these devices symmetrically increase and decrease the elliptical area size as audio amplitude increases and decreases, nor are there means disclosed for horizontally shifting the pattern center by 180.degree. to create hyperbolic areas out of the elliptical areas. Additionally, none of these devices provide means to interrupt horizontal synchronizing pulses in order to create a jagged pattern edge.
There are additional video displaying circuits such as used with television gaming apparata. These apparata use operator input commands and signals to move such items as bars (representative of a ping pong paddle) or balls into various positions for the purpose of playing a game against an opponent. The following two patents are representative of such game apparata:
______________________________________ Patent No. Patentee Issue Date ______________________________________ 3,659,284 Rusch 4/25/72 3,659,285 Baer et al. 4/25/72 ______________________________________
These two patents are not audio to video devices and although patterns are displayed on a television receiver, their applicability to the art of the present invention is limited.